Are you sitting comfortably?

Alex Michaelis is an archetypal London architect. Linen shirt, strong hands, zipping from desk to desk in his former-church-hall office with its industrial lighting, white desks and parquet flooring. Today he is particularly fired up: his practice—Michaelis Boyd, founded with Tim Boyd in 1995—has landed the job of designing flats for the multi-million-pound conversion of Battersea Power Station. The pair have projects around the world (Michaelis is just off the red-eye from Johannesburg) and get plenty of work from the west-London elite—they bolted the now-infamous wind turbine onto David Cameron’s old home. So what is he doing messing around with chairs?

“I love chairs. In my house I have a huge number that I love—and, yes,” he admits, “it’s all the architect ones.” By this, he means what others might call design classics: Mies van der Rohe’s Barcelona chair, Le Corbusier’s Grand Confort, Eero Saarinen’s Womb chair. Even if you’re not familiar with their names, you’ll have seen them. Acres of travertine-floored lobby are scattered with the slack, steel X of the Barcelona, while the Womb, as enveloping as its name suggests, is a favourite of expensive hotels. Though these chairs are more than 60 years old, all are still in production—and all were designed by architects.

Pretty much every architect in the alphabet has produced a chair, a miniature version of their particular aesthetic. Frank Gehry’s Wiggle side chair is all playful corrugated cardboard; Norman Foster’s 20-06 Stacker is more characteristically ascetic. Zaha Hadid’s Z-chair is an evocative, egotistical zig-zag of stainless steel, reportedly fetching upwards of £150,000. Most recently, David Adjaye’s Washington designs for the furniture manufacturer Knoll are a seemingly wilful complication—why have a leg on each corner when you can cantilever the seat and add support struts? Buildings are all very well, but it seems you haven’t truly made it as an architect until you’ve given us something to sit on.

And we can’t get enough of them. As the celebrity of architects grows, products with their names attached become ever more attractive—and expensive. Recently, Phillips auction house devoted an entire sale to “The Architect”, with furniture lots including a fluid, cantilevered armchair by Alvar Aalto from 1931, sold for £23,750, and a prototype of an aluminium stackable chair by Alfred Roth, sold for £31,250.

Alex Michaelis is sitting on his firm’s Dinner for 8 chair. Reminiscent of the tubular metal P.E.L./Cox stackable chairs, designed in the 1930s and still found in various iterations in schools across Britain, the Michaelis Boyd chair is more refined, more intimate, with narrower tubing and a tactile, coloured-felt seat and back. What made someone trained for seven years to put a roof over our heads want to make furniture? “Mentally, it’s a very good exercise, to go from [designing] a building to the smallest bit in a building,” he says. “You go back to the detail of the human body.”

There’s also the nature of the chair as an experiment, a playground. As Zoë Ryan, the curator of architecture and design at the Art Institute of Chicago, explains: “It’s a means for architects to illustrate their ideas in a way they couldn’t in a full-blown building. Furniture is more immediate, it gives them something to play with. It becomes another expression of their ideas, and architects love to do it all.”

Greg Lynn certainly loves to do it all. An American architect known both for the bulging forms of his “blobitechture” and his zealous pursuit of innovation, Lynn has turned his pen to everything from jewellery to yachts. He speaks to me from his Los Angeles studio where he’s sitting in a prototype of his Ravioli chair. A kind of knit-covered amoeba, made for the Swiss company Vitra in 2005, this is considered so important that it is now in the permanent collection at the Museum of Modern Art in New York. “[A chair] is a good place to look at new materials. And also new ergonomics,” Lynn says. “The Ravioli chair allowed me to practise, at an intricate scale, ideas about materials and assembly. An architect will use furniture for that a lot.”

The history of architect-designed chairs goes back as far as architecture itself—it wouldn’t have occurred to early practitioners to confine themselves to buildings. But it was in the 20th century, with the advent of Modernism, that the practice flourished. Until then, chairs were essentially carpenter’s pieces: hand-crafted, decorative, elaborate. Such traditional, heavy wooden furniture had no place in the glazed, day-lit, pared-back spaces created by the likes of Mies and Le Corbusier. Design as a separate discipline didn’t yet exist, so the Modernist architects knew that if they wanted suitable furniture for their great works, they would have to create it; chairs became mini-manifestos of their ideas. The house was a machine for chairs to live in.

By the 1950s, design schools began to appear, pumping out graduates specifically trained to make furniture. This is when you start to see the rise of pieces such as the Wishbone chair by Hans Wegner (who started as a carpenter’s apprentice), or Robin Day’s Hille polypropylene stacking chair. While it became rarer for an architect to be commissioned to make furniture as well as the building to put it in, big-name architects were—and still are—frequently approached with commissions by the likes of Knoll or Vitra. Greg Lynn believes these companies call on architects when they want to change direction. “To help them shake things up, to rethink materials, to rethink manufacturing process, to rethink ergonomics. Usually they’ll then kick the architects out and have industrial designers figure out what to do with it all. We’re necessary, but they hate us.”

How necessary? Zeev Aram, who founded his deeply influential contemporary furniture store 50 years ago, knows what makes a chair work. His shop in central London is a tour through more than a century of chairs: some by architects, but many, too, by industrial designers such as Bertoia. And, crucially, several by Charles and Ray Eames, the American husband-and-wife team whose backgrounds combined architectural training with design practice.

Seated in an Eames DAR—a fabric-lined cup of moulded fibreglass on a star base—Aram tells me he believes “architecture is the most important study one can do, even if one never practises it, because it touches on all aspects of life.” But he doesn’t see architects as having any special place in chair design. Instead he says that the key to a good product is the designer’s relationship with his manufacturer, a “tango” which can make or strangle an idea. He cites the American firm Herman Miller as one that has most successfully danced that tango.

For more than 80 years Herman Miller has made, among other classics, arguably the most coveted chair of the lot—the Eameses’ padded leather Lounge chair. Continuously in production since 1956, this is a chair that has spawned books, been the subject of an entire exhibition, and become shorthand for status and smartness, while simultaneously being traditional enough to be unthreatening. Complete with its matching ottoman, the Lounge chair is very much a product of baby-boomer America, speaking of a country with space, natural resources and affluence to luxuriate in.

Last autumn, I visited the Herman Miller headquarters in Zeeland, Michigan, the heartland of America’s furniture industry. The company’s guesthouse, Marigold Lodge, was filled with Tiffany lamps and Eames Lounges, alongside a menagerie of other Eames designs. Among them are the Executive (commonly known as the “Time Life”, so heavily is it associated with the company whose offices it was designed for) and the Soft Pad—the spotlit, black leather seat from the tv quiz show “Mastermind”. Seeing it in the lodge, you’re left in no doubt why the Soft Pad is such a success. Happy in any context, as beautiful empty as occupied, great on its own, even better in numbers. And boy is it comfortable.

Visual appeal does not necessarily translate into comfort, and architect-designed chairs have a reputation for being better to look at than sit on. Mies’s Barcelona chair, first marketed by Knoll, remains a lobby staple, but anyone waiting for an interview knows better than to sit in one—the struggle to get out of its deep angles when the call finally comes is not something you’d want your next boss to witness. It is the type of chair that Knoll’s design director, Benjamin Pardo, describes as something “everyone wants to be photographed stood next to”.

At the Genesis factory down the road from Zeeland, where many of Herman Miller’s Eames products are hand-machined, a factory of skilled labourers—rolling around on rejected examples of £3,000 Soft Pads—are checking leather for flaws, stitching, stuffing, bonding, turning. Mike Kuperus runs the factory and has worked every station. He says when you work on a piece of furniture, you can tell what kind of designer was behind it: for Kuperus a good designer is as interested in how an item is put together as in how it looks. An entire cowhide is required to produce a single Eames Lounge chair. This is in stark contrast to the bestselling, mesh-backed, and 94% recyclable Aeron office chair, which costs around £900 and can be assembled on the Herman Miller production line in just 17 seconds. Like the Lounge, the 20-year-old Aeron has a place in MOMA’s permanent collection in New York; unlike the Lounge, it was created by Bill Stumpf and Don Chadwick—not architects, but industrial designers.

Konstantin Grcic is an industrial designer; he’s also good at tangos. The man behind one of the few chairs that could convincingly be described as modern classics—the cast aluminium and concrete Chair_ONE for Magis—Grcic has had successful collaborations with several other manufacturers, including Authentics, Flos and Vitra, producing everything from bags to pressure cookers.

Born in Munich in 1965, Grcic, who trained as a cabinetmaker before studying design at the Royal College of Art in London, is firmly in the Kuperus-approved category—a designer concerned with construction and materials, rather than simply the form of the finished product. The difference stems from their training. Study design and you get your hands dirty: your ideas are made into prototypes, and possibly even finished products. Architecture students, whose discipline is more theoretical, have clean hands. Despite all this, Grcic believes that architects can bring something to the chair that product and industrial designers do not. “As industrial designers, our concern for the object means we tend to overdo things,” he says, on the phone from his studio in Munich. “The architect is interested in a chair being almost an architecture, almost a skeleton, very pared-down.”

It’s a view echoed by Alex Michaelis: “There isn’t much difference between designing a chair and a building. Both are about taking a brief, paring it down to the barest simplicity, then seeing where you are.”

“It’s interesting that the Modernist chairs—the key reference points for the modern chair—were designed by architects,” Grcic agrees. “They needed to furnish what they built, and they understood about this big change in society. They wanted to find new answers.” This, he notes, is in contrast to some recent chairs, which he feels are more likely to be the child of marketing than of ideology: branding exercises, like a fashion house putting its logo on a perfume. This might explain why Grcic feels few of today’s biggest architects have designed a truly great chair. “There’s a chair by Norman Foster, he’s a great architect but it’s appalling. Herzog & de Meuron haven’t designed a chair because they haven’t dared. Renzo Piano, great architect, hasn’t designed a chair as far as I know.” In truth, Piano has given us his chair: wooden, square-backed, and entirely unremarkable. Perhaps that’s why Grcic didn’t notice it.

Whoever makes them, don’t we already have enough chairs to choose from? Not according to Zeev Aram. “Ever since man cut a log and said ‘that’s quite a good stool to sit on’, the variations are enormous. All these chairs are a compromise. Each designer compromises in his own way, and [a good chair] comes down to talent and imagination. I don’t care if it’s an architect, I don’t care if it’s a road-sweeper, as long as they can design something.”

Does Grcic feel any rivalry between designers and architects (or, indeed, road-sweepers)? “I’m happy for every good chair I see. It means the whole evolution, the discussion, the dreaming about chairs continues.”